How this site measures the dollar

Kenya has one dollar, and two published rates that sit within a fraction of a per cent of each other. This page explains where each figure comes from, how it is checked, and what this site refuses to print.

One dollar, two rates

The dollar is one currency, but it has two prices in Kenya. The Central Bank publishes a weighted average of interbank trades each trading day; the open market quotes a price for a stablecoin settled through M-Pesa or bank transfer. The gap between them is the shilling difference, shown as a percentage of the CBK rate. That gap is small, and it moves little from day to day.

A small gap does not mean a reader loses nothing. The rate a bank or bureau gives a customer sits on one side of both figures: a buying rate below and a selling rate above. The spread between those two is the cost of exchanging cash, and it is larger than the gap between the two published rates.

The CBK rate

The official rate is the Central Bank of Kenya’s weighted average of registered spot trades in the interbank foreign exchange market, published once per trading day. This site reads the data behind the CBK’s forex page, not the cached text, to get the latest figure. The CBK does not set the rate; it reports what the interbank market did.

The CBK publishes no row for weekends and holidays. A day appears in the day-by-day table with an open-market figure only if this site took a reading on it. The CBK rate is not a rate any bank or bureau must give a customer; it is a benchmark that individual institutions set their own rates around.

The open-market rate

The open-market rate is the median of Binance P2P advertisements for USDT priced in shillings, using advertisers with an order history and dropping advertisements far from the median of their side. It is a stablecoin price settled through M-Pesa or bank transfer, not a banknote price and not a survey of forex bureaux.

Because the open-market series continues through weekends and holidays, a day can show an open-market figure without a CBK row. This site’s own record starts short and grows as readings are taken. The open-market rate is live every day, but it is not a rate at which dollars can be bought or sold in cash.

What this site refuses to print

The CBK’s own list of forex-bureau rates is a set of documents whose newest entry is years old, so no bureau rate is shown. The bank board read here, NCBA’s indicative USD rates, is recorded but never used in the gap: its date moves daily while its buying and selling figures stay the same for weeks, and the site marks it frozen when it equals the same board two weeks earlier.

A reading is refused if the CBK rate is outside a plausible band or more than five days old, if the open-market rate leaves a band of minus three to plus six per cent against the CBK rate or rests on too few advertisements, or if the CBK rate differs from an independent exchange-rate source by more than two and a half per cent. No forecast is made. The site records the rates it has seen and shows them as they were published.